Sun-Uck Kwon

High resolution MRI difference between moyamoya disease and intracranial atherosclerosis

Along with intracranial atherosclerotic disease (ICAD), moyamoya disease (MMD) is the most common cause of middle cerebral artery (MCA) occlusion in Asians. Although they have differing vascular wall pathologies, conventional angiographic evaluation methods cannot easily differentiate MMD from ICAD in certain situations, such as in young patients with atherosclerotic risk factors. High resolution magnetic resonance imaging (HR‐MRI) findings for the diseased segments of MCAs in MMD and symptomatic ICAD were compared to further elucidate differences in arterial wall changes.

Basilar artery atherosclerotic disease is related to subacute lesion volume increase in pontine base infarction

Background –  Although basilar artery atherosclerotic disease (BAD) is frequent in patients with pontine base infarction, it remains unknown whether BAD is related to the lesion size or clinical outcome.

MRI evidence of reperfusion injury associated with neurological deficits after carotid revascularization procedures

Background and purpose:  Some patients develop major neurological complications after carotid revascularization procedures, despite the lack of new infarcts or classical hyperperfusion syndrome.

Outcomes after endovascular treatment of symptomatic patients with Takayasu's arteritis.

We report our experience with endovascular treatment of supra-aortic arteries and follow-up results in patients with Takayasus arteritis (TA) presenting with neurological symptoms. Of the 20 patients with TA who underwent cerebral angiography for neurological manifestations between May 2002 and May 2009, 12 (11 females, one male; mean age, 39 years; range 31–56 years) underwent endovascular treatment and evaluated outcome for 21 lesions, including nine common carotid arteries, four vertebral arteries, four subclavian arteries, two internal carotid arteries, and one brachiocephalic artery. Eight patients underwent multiple endovascular procedures for different lesions in single or multiple stages. Mean angiographic and clinical follow-up durations were 34 months (range, 11–79 months) and 39 months (range 11–91 months), respectively. Technical success was achieved for 20 procedures in 11 patients. One procedure failed, with 50% residual stenosis after stenting due to dense calcification of vessel walls. There were no procedure-related complications. Restenosis occurred at two lesions in two patients were treated by re-stenting. Asymptomatic occlusion occurred at two lesions in one patient. Ten patients remained in 0–1 on the modified Rankin scale (mRs) during mean 39 months. One patient, however, had a score of 3 on mRs due to a traumatic contusion during follow-up. One patient died from cardiac failure 36 months after successful angioplasty. Our data suggest that endovascular treatment of symptomatic supra-aortic lesions of TA is effective and durable in selected patients with neurologic symptoms.

Internal carotid artery stenosis with ipsilateral persistent hypoglossal artery presenting as a multiterritorial embolic infarction: a case report

Persistent hypoglossal artery (PHA) is a relatively rare vascular anomaly of persistent carotid-basilar anastomosis. We have treated a patient with stenosis of the internal carotid artery which was combined with PHA and who presented with multiple small embolic infarcts in multiple vascular territories. It is important to know that a persistent carotid-basilar anastomosis could be one of the causes bringing about acute infarction in both the anterior and posterior vascular territories, mimicking cardioembolism.

Effect of cilnidipine vs losartan on cerebral blood flow in hypertensive patients with a history of ischemic stroke: a randomized controlled trial

Objectives –  The aim of this study was to compare the effects of antihypertensive agents on cerebral blood flow (CBF) in hypertensive patients with previous ischemic stroke.

Age and body weight adjusted warfarin initiation program for ischaemic stroke patients.

Background:  Despite its proven effect, anticoagulation is not recommended to the acute ischaemic stroke due to the risk of bleeding complications. The purpose of this study is development of individualized warfarin initiation program for acute or subacute stroke patients.

Stroke recurrence patterns are predicted by the subtypes and mechanisms of the past, non-cardiogenic stroke.

The association between past stroke subtypes and recurrent stroke subtypes in non‐cardiogenic stroke remains unknown.

Change of Platelet Reactivity to Antiplatelet Therapy after Stenting Procedure for Cerebral Artery Stenosis: VerifyNow Antiplatelet Assay before and after Stenting.

Purpose VerifyNow antiplatelet assays were performed before and after stenting for various cerebral artery stenoses to determine the effect of the procedure itself to the function of dual antiplatelets given. Materials and Methods A total of 30 consecutive patients underwent cerebral arterial stenting procedure were enrolled. The antiplatelet pretreatment regimen was aspirin (100 mg daily) and clopidogrel (300 mg of loading dose followed by 75mg daily). VerifyNow antiplatelet assay performed before and right after stenting. The two test results were compared in terms of aspirin-reaction unit (ARU), P2Y12 reaction units (PRU), baseline (BASE), and percentage inhibition. We evaluated occurrence of any intra-procedural in-stent thrombosis or immediate thromboembolic complication, and ischemic events in 1-month follow-up. Results The median Pre-ARU was 418 (range, 350-586). For clopidogrel the medians of the pre-BASE, PRU, and percent inhibition were 338 (279-454), 256 (56-325), and 27% (0-57%). The medians of the post-ARU, BASE, PRU, and percent inhibition after stenting were 469 (range, 389-573), 378 (288-453), 274 (81-370), and 26% (0-79%). There was a significant increase of ARU (p=0.045), BASE (p=0.026), and PRU (p=0.018) before and after stenting. One immediate thromboembolic event was observed in poor-response group after stenting. There was no in-stent thrombosis and ischemic event in 1-month follow-up. Conclusion We observed a significant increase of platelet reactivity to dual antiplatelet therapy right after stenting procedure for various cerebral arterial stenoses.

High prevalence of unrecognized cerebral infarcts in first-ever stroke patients with cardioembolic sources

Background:  With magnetic resonance imaging (MRI) analysis, we investigated the prevalence, clinical significance, and factors related to the presence of unrecognized cerebral infarcts in patients with first‐ever ischaemic stroke.